Computers and other similar systems have now invaded virtually every area of human endeavor, most being equipped with a Graphic User Interface (GUI). GUI assumes that the user thereof is equipped with what is generically referred to as a remote control device. Pointing devices are a form of remote control device and are used, among many other uses, to move a cursor around on a computer screen. In addition to providing a cursor movement function, pointing devices are typically equipped with one or more switches, buttons or similar devices that allow signals to be sent to a processor for interpretation into a command or commands for positioning a computer cursor or other computer controlled functions.
The earliest and probably still the most widely used pointing device is the ubiquitous “mouse”. A mouse typically has a contoured housing that rests under the palm and fingers of the user's hand having a flat bottom surface equipped with a ball, a light or other mechanism which moves or interprets movement on a flat surface. A mechanism inside the mouse generates signals corresponding to the movement of the mouse in both the X and Y directions on the flat surface. It has been established by the medical research that the extended use of a mouse may lead to or aggravate carpel tunnel syndrome (CTS). The movement of such a mouse of the prior art requires a great deal of arm and hand motion, typically from the user's shoulder outward. This precludes the use of such a device by a person having a variety of physical disabilities where there is restricted movement of the arm, hand and fingers.
Another widely used class of pointing devices is called a trackball device. In operation, a trackball may be envisioned as an inverted mouse where the ball resides on the top surface of the device rather than on the bottom surface. A user directly manipulates the ball typically with finger, hand and wrist action to generate X and Y control signals similar to those generated by a mouse. Track ball devices typically require relatively less movement than do mice. And, because they do not rely on a flat surface nor do they require a surface area for movement for operation, track balls may be placed in a possibly more convenient location relative to their users. Trackball devices still require that users move their arm, hand and fingers repeatedly, although in a more fixed position than with a standard mouse. Even the reduced movement required to use a trackball may possibly, with constant repetition, cause or contribute to CTS. A track ball also restricts its user to the given area where the track ball sits or resides.
It would appear desirable to provide a control device which did not require that a user maintain a constant, fixed physical relationship to the fixed surface upon which the pointing device is manipulated or required to reside. The control device of the present invention allows the user substantially unrestricted flexibility in positioning himself or herself relative to the device being controlled.